Nrpe - connection refused by host

I have some troubles with a RHEL 4.5 host installing nrpe.
After compiling and installing nagios-plugins v. 1.4.11 and nrpe 2.11, when I execute the command:

./check_nrpe - H localhost

I got the message: Connection refused by host

nrpe is configured to work via xinetd and the netstat command shows the port in status LISTEN.
Also I have set debug=1 but no messages appeared in /var/log/messages.

I have 4 RHEL 4.5 more hosts configured and working OK with the same configuration. No iptables run in this server.

Any ideas?

can you telnet to that port: telnet localhost 5666

Also, do you have /etc/hosts.allow and /etc/hosts.deny configured? If so, that can cause issues.

Also, make sure you allow connections from localhost in your /etc/xinetd.d/nrpe file